1. Field of the Invention
The embodiments of the present invention relate generally to structures and methods for extracting nucleic acids from multicomponent samples. The structures and methods of embodiments of the invention are suitable for incorporation into micro and nano fluidic devices, such as lab-on-a-chip devices and micro total analysis systems.
2. Background Information
Genetic information in living organisms is contained in the form of very long nucleic acid molecules such as deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Naturally occurring DNA and RNA molecules are typically composed of repeating chemical building blocks called nucleotides which are in turn made up of a sugar (deoxyribose or ribose, respectively), phosphoric acid, and one of four bases, adenine (A), cytosine (C), guanine (G), and thymine (T) or uracil (U). The human genome, for example, contains approximately three billion nucleotides of DNA sequence and an estimated 20,000 to 25,000 genes. DNA sequence information can be used to determine multiple characteristics of an individual as well as the presence of and or susceptibility to many common diseases, such as cancer, cystic fibrosis, and sickle cell anemia. Determination of the entire three billion nucleotide sequence of the human genome has provided a foundation for identifying the genetic basis of such diseases. Sequencing the genomes of individuals provides an opportunity to personalize medical treatments. The need for nucleic acid sequence information also exists in research, environmental protection, food safety, biodefense, and clinical applications, such as for example, pathogen detection (the detection of the presence or absence of pathogens or their genetic varients).
Accurate and precise separation of different molecules from one another is important in situations in which a small number of desired molecules are present as a mixture of several components in a small volume solution, such as, for example, in the context of analytical and diagnostic testing. Samples used in diagnostic tests, such as, for example bodily fluids and tissue samples, are typically mixtures of a variety of components. In order to perform accurate tests, the desired molecules must typically be separated from the components of the mixture. There remains a need to improve the efficiencies of such separations and, thereby, the convenience to researchers working in the chemical and biological sciences.
Because DNA sequencing is an important technology for applications in bioscience, such as, for example, the analysis of genetic information content for an organism, tools that allow for faster and or more reliable sequence determination are valuable. Applications such as, for example, population-based biodiversity projects, disease detection, personalized medicine, prediction of effectiveness of drugs, and genotyping using single-nucleotide polymorphisms, stimulate the need for simple and robust methods for sequencing nucleic. Methods and devices that provide increased accuracy and or robustness, decreased need for analysis sample, and or high throughput are valuable analytical and biomedical tools.